paulxstretch/deps/juce/modules/juce_audio_utils/gui/juce_AudioAppComponent.h

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/*
==============================================================================
This file is part of the JUCE library.
Copyright (c) 2020 - Raw Material Software Limited
JUCE is an open source library subject to commercial or open-source
licensing.
By using JUCE, you agree to the terms of both the JUCE 6 End-User License
Agreement and JUCE Privacy Policy (both effective as of the 16th June 2020).
End User License Agreement: www.juce.com/juce-6-licence
Privacy Policy: www.juce.com/juce-privacy-policy
Or: You may also use this code under the terms of the GPL v3 (see
www.gnu.org/licenses).
JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
DISCLAIMED.
==============================================================================
*/
namespace juce
{
//==============================================================================
/**
A base class for writing audio apps that stream from the audio i/o devices.
Conveniently combines a Component with an AudioSource to provide a starting
point for your audio applications.
A subclass can inherit from this and implement just a few methods such as
getNextAudioBlock(). The base class provides a basic AudioDeviceManager object
and runs audio through the default output device.
An application should only create one global instance of this object and multiple
classes should not inherit from this.
This class should not be inherited when creating a plug-in as the host will
handle audio streams from hardware devices.
@tags{Audio}
*/
class JUCE_API AudioAppComponent : public Component,
public AudioSource
{
public:
AudioAppComponent();
AudioAppComponent (AudioDeviceManager&);
~AudioAppComponent() override;
/** A subclass should call this from their constructor, to set up the audio. */
void setAudioChannels (int numInputChannels, int numOutputChannels, const XmlElement* const storedSettings = nullptr);
/** Tells the source to prepare for playing.
An AudioSource has two states: prepared and unprepared.
The prepareToPlay() method is guaranteed to be called at least once on an 'unprepared'
source to put it into a 'prepared' state before any calls will be made to getNextAudioBlock().
This callback allows the source to initialise any resources it might need when playing.
Once playback has finished, the releaseResources() method is called to put the stream
back into an 'unprepared' state.
Note that this method could be called more than once in succession without
a matching call to releaseResources(), so make sure your code is robust and
can handle that kind of situation.
@param samplesPerBlockExpected the number of samples that the source
will be expected to supply each time its
getNextAudioBlock() method is called. This
number may vary slightly, because it will be dependent
on audio hardware callbacks, and these aren't
guaranteed to always use a constant block size, so
the source should be able to cope with small variations.
@param sampleRate the sample rate that the output will be used at - this
is needed by sources such as tone generators.
@see releaseResources, getNextAudioBlock
*/
void prepareToPlay (int samplesPerBlockExpected,
double sampleRate) override = 0;
/** Allows the source to release anything it no longer needs after playback has stopped.
This will be called when the source is no longer going to have its getNextAudioBlock()
method called, so it should release any spare memory, etc. that it might have
allocated during the prepareToPlay() call.
Note that there's no guarantee that prepareToPlay() will actually have been called before
releaseResources(), and it may be called more than once in succession, so make sure your
code is robust and doesn't make any assumptions about when it will be called.
@see prepareToPlay, getNextAudioBlock
*/
void releaseResources() override = 0;
/** Called repeatedly to fetch subsequent blocks of audio data.
After calling the prepareToPlay() method, this callback will be made each
time the audio playback hardware (or whatever other destination the audio
data is going to) needs another block of data.
It will generally be called on a high-priority system thread, or possibly even
an interrupt, so be careful not to do too much work here, as that will cause
audio glitches!
@see AudioSourceChannelInfo, prepareToPlay, releaseResources
*/
void getNextAudioBlock (const AudioSourceChannelInfo& bufferToFill) override = 0;
/** Shuts down the audio device and clears the audio source.
This method should be called in the destructor of the derived class
otherwise an assertion will be triggered.
*/
void shutdownAudio();
AudioDeviceManager& deviceManager;
private:
//==============================================================================
AudioDeviceManager defaultDeviceManager;
AudioSourcePlayer audioSourcePlayer;
bool usingCustomDeviceManager;
JUCE_DECLARE_NON_COPYABLE_WITH_LEAK_DETECTOR (AudioAppComponent)
};
} // namespace juce